layer23 bursts - strategy for filtering IA's for tmsi based on downlink traffic only?
Hi all, I am running some tests/experiments with the burst_ind branch. I want to be able to only follow the immediate assignments for my TMSI as it is difficult to verify that the bursts are indeed my traffic. However, I suspect this is not possible using only downlink traffic as without the channel request from the MS I cannot match the resulting IA? I would need to capture uplink too? I would be grateful if someone could confirm if this is the case or if there is a way around this issue? Many thanks, Matt.
I am using a GSM900/1800/1900 handset (GTA02), and want it to be able to receive on the GSM850 band as well. This is a challenge I want to take on. Has this been done already? Is is physically possible? Ideas for where to start? Thanks, Uri
On Wed, 23 Feb 2011 09:53:34 +0000 (GMT), MATTHEW EVANS wrote:
I am running some tests/experiments with the burst_ind branch. I want to be able to only follow the immediate assignments for my TMSI as it is difficult to verify that the bursts are indeed my traffic. However, I suspect this is not possible using only downlink traffic as without the channel request from the MS I cannot match the resulting IA? I would need to capture uplink too?
Even if you would capture the uplink on the RACH you would not be able to distinguish your phones request using your tmsi because IAs refer to requests by their Random Reference (04.08, 9.1.8). Only if you knew this reference you could follow only your phones DCHs. The first time a tmsi/imsi may be sent is on an already established DCH. Of course you could still implement something that only if a RACH request is received on uplink the IA is followed, so you could be sure to follow only requests from phones in your vicinity. Regards, Mad
participants (3)
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Mad -
MATTHEW EVANS -
Uri Savoray